staging: greybus: fix stack size warning with UBSAN

clang warns about excessive stack usage in this driver when
UBSAN is enabled:

drivers/staging/greybus/audio_topology.c:977:12: error: stack frame size of 1836 bytes in function 'gbaudio_tplg_create_widget' [-Werror,-Wframe-larger-than=]

Rework this code to no longer use compound literals for
initializing the structure in each case, but instead keep
the common bits in a preallocated constant array and copy
them as needed.

Link: https://github.com/ClangBuiltLinux/linux/issues/1535
Link: https://lore.kernel.org/r/20210103223541.2790855-1-arnd@kernel.org/
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
[nathan: Address review comments from v1]
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/r/20211209195141.1165233-1-nathan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/greybus/audio_topology.c b/drivers/staging/greybus/audio_topology.c
index 1e613d4..7f7d558 100644 (file)
--- a/drivers/staging/greybus/audio_topology.c
+++ b/drivers/staging/greybus/audio_topology.c
@@ -974,6 +974,44 @@ static int gbaudio_widget_event(struct snd_soc_dapm_widget *w,
        return ret;
 }
 
+static const struct snd_soc_dapm_widget gbaudio_widgets[] = {
+       [snd_soc_dapm_spk]      = SND_SOC_DAPM_SPK(NULL, gbcodec_event_spk),
+       [snd_soc_dapm_hp]       = SND_SOC_DAPM_HP(NULL, gbcodec_event_hp),
+       [snd_soc_dapm_mic]      = SND_SOC_DAPM_MIC(NULL, gbcodec_event_int_mic),
+       [snd_soc_dapm_output]   = SND_SOC_DAPM_OUTPUT(NULL),
+       [snd_soc_dapm_input]    = SND_SOC_DAPM_INPUT(NULL),
+       [snd_soc_dapm_switch]   = SND_SOC_DAPM_SWITCH_E(NULL, SND_SOC_NOPM,
+                                       0, 0, NULL,
+                                       gbaudio_widget_event,
+                                       SND_SOC_DAPM_PRE_PMU |
+                                       SND_SOC_DAPM_POST_PMD),
+       [snd_soc_dapm_pga]      = SND_SOC_DAPM_PGA_E(NULL, SND_SOC_NOPM,
+                                       0, 0, NULL, 0,
+                                       gbaudio_widget_event,
+                                       SND_SOC_DAPM_PRE_PMU |
+                                       SND_SOC_DAPM_POST_PMD),
+       [snd_soc_dapm_mixer]    = SND_SOC_DAPM_MIXER_E(NULL, SND_SOC_NOPM,
+                                       0, 0, NULL, 0,
+                                       gbaudio_widget_event,
+                                       SND_SOC_DAPM_PRE_PMU |
+                                       SND_SOC_DAPM_POST_PMD),
+       [snd_soc_dapm_mux]      = SND_SOC_DAPM_MUX_E(NULL, SND_SOC_NOPM,
+                                       0, 0, NULL,
+                                       gbaudio_widget_event,
+                                       SND_SOC_DAPM_PRE_PMU |
+                                       SND_SOC_DAPM_POST_PMD),
+       [snd_soc_dapm_aif_in]   = SND_SOC_DAPM_AIF_IN_E(NULL, NULL, 0,
+                                       SND_SOC_NOPM, 0, 0,
+                                       gbaudio_widget_event,
+                                       SND_SOC_DAPM_PRE_PMU |
+                                       SND_SOC_DAPM_POST_PMD),
+       [snd_soc_dapm_aif_out]  = SND_SOC_DAPM_AIF_OUT_E(NULL, NULL, 0,
+                                       SND_SOC_NOPM, 0, 0,
+                                       gbaudio_widget_event,
+                                       SND_SOC_DAPM_PRE_PMU |
+                                       SND_SOC_DAPM_POST_PMD),
+};
+
 static int gbaudio_tplg_create_widget(struct gbaudio_module_info *module,
                                      struct snd_soc_dapm_widget *dw,
                                      struct gb_audio_widget *w, int *w_size)
@@ -1052,77 +1090,37 @@ static int gbaudio_tplg_create_widget(struct gbaudio_module_info *module,
 
        switch (w->type) {
        case snd_soc_dapm_spk:
-               *dw = (struct snd_soc_dapm_widget)
-                       SND_SOC_DAPM_SPK(w->name, gbcodec_event_spk);
+               *dw = gbaudio_widgets[w->type];
                module->op_devices |= GBAUDIO_DEVICE_OUT_SPEAKER;
                break;
        case snd_soc_dapm_hp:
-               *dw = (struct snd_soc_dapm_widget)
-                       SND_SOC_DAPM_HP(w->name, gbcodec_event_hp);
+               *dw = gbaudio_widgets[w->type];
                module->op_devices |= (GBAUDIO_DEVICE_OUT_WIRED_HEADSET
                                        | GBAUDIO_DEVICE_OUT_WIRED_HEADPHONE);
                module->ip_devices |= GBAUDIO_DEVICE_IN_WIRED_HEADSET;
                break;
        case snd_soc_dapm_mic:
-               *dw = (struct snd_soc_dapm_widget)
-                       SND_SOC_DAPM_MIC(w->name, gbcodec_event_int_mic);
+               *dw = gbaudio_widgets[w->type];
                module->ip_devices |= GBAUDIO_DEVICE_IN_BUILTIN_MIC;
                break;
        case snd_soc_dapm_output:
-               *dw = (struct snd_soc_dapm_widget)SND_SOC_DAPM_OUTPUT(w->name);
-               break;
        case snd_soc_dapm_input:
-               *dw = (struct snd_soc_dapm_widget)SND_SOC_DAPM_INPUT(w->name);
-               break;
        case snd_soc_dapm_switch:
-               *dw = (struct snd_soc_dapm_widget)
-                       SND_SOC_DAPM_SWITCH_E(w->name, SND_SOC_NOPM, 0, 0,
-                                             widget_kctls,
-                                             gbaudio_widget_event,
-                                             SND_SOC_DAPM_PRE_PMU |
-                                             SND_SOC_DAPM_POST_PMD);
-               break;
        case snd_soc_dapm_pga:
-               *dw = (struct snd_soc_dapm_widget)
-                       SND_SOC_DAPM_PGA_E(w->name, SND_SOC_NOPM, 0, 0, NULL, 0,
-                                          gbaudio_widget_event,
-                                          SND_SOC_DAPM_PRE_PMU |
-                                          SND_SOC_DAPM_POST_PMD);
-               break;
        case snd_soc_dapm_mixer:
-               *dw = (struct snd_soc_dapm_widget)
-                       SND_SOC_DAPM_MIXER_E(w->name, SND_SOC_NOPM, 0, 0, NULL,
-                                            0, gbaudio_widget_event,
-                                            SND_SOC_DAPM_PRE_PMU |
-                                            SND_SOC_DAPM_POST_PMD);
-               break;
        case snd_soc_dapm_mux:
-               *dw = (struct snd_soc_dapm_widget)
-                       SND_SOC_DAPM_MUX_E(w->name, SND_SOC_NOPM, 0, 0,
-                                          widget_kctls, gbaudio_widget_event,
-                                          SND_SOC_DAPM_PRE_PMU |
-                                          SND_SOC_DAPM_POST_PMD);
+               *dw = gbaudio_widgets[w->type];
                break;
        case snd_soc_dapm_aif_in:
-               *dw = (struct snd_soc_dapm_widget)
-                       SND_SOC_DAPM_AIF_IN_E(w->name, w->sname, 0,
-                                             SND_SOC_NOPM,
-                                             0, 0, gbaudio_widget_event,
-                                             SND_SOC_DAPM_PRE_PMU |
-                                             SND_SOC_DAPM_POST_PMD);
-               break;
        case snd_soc_dapm_aif_out:
-               *dw = (struct snd_soc_dapm_widget)
-                       SND_SOC_DAPM_AIF_OUT_E(w->name, w->sname, 0,
-                                              SND_SOC_NOPM,
-                                              0, 0, gbaudio_widget_event,
-                                              SND_SOC_DAPM_PRE_PMU |
-                                              SND_SOC_DAPM_POST_PMD);
+               *dw = gbaudio_widgets[w->type];
+               dw->sname = w->sname;
                break;
        default:
                ret = -EINVAL;
                goto error;
        }
+       dw->name = w->name;
 
        dev_dbg(module->dev, "%s: widget of type %d created\n", dw->name,
                dw->id);